JEE Main & Advanced
Sample Paper
JEE Main - Mock Test - 18
question_answer
The activity of a freshly prepared radioactive sample is \[{{10}^{10}}\]disintegrations per second, whose mean life is \[{{10}^{9}}\] s. The mass of an atom of this radioisotope is\[{{10}^{-25}}\] kg. The mass of the radioactive sample is ____ mg.